Method of making tread members with friction inserts



Patented Jan. 3, 1939 v UNITED STATES PATENT OFFICE 1\IETHOD OF MAKJNG TREAD I\IEI\IBERS WI'IH FRICTION INSERTS Arthur Greenbaum, Beachmont, Mass., assignor to Panther-Panco Rubber C'o., Inc. Chelsea, Mass., a, corporation of Massachusetts Application Decemher 15, 1936, Serial N0. 115,981

1 Olaim. (C1. 12-146) The present inventicn re1ates to the production and the cut-out sole blank assembled therewith, I cf friction soles and heels of rubber compound, attach a sheec of rubber which on the attaching and is more particularly concerned. With articles face of the finished sole completely covers the fore of this character employing an imbedded fibre part of t-he sole including the juncture of the sole 5 which is presented in endwise relationship to the and insert. 5 tread of the member. This arrangement is clearly illustrated in the I1: is the object of the present invention to sucdrawing, in which represents the sole blank cessfully embody friction inserts Within rubber properly died out to receive the insert the comso1es and heels cf varying characteristics in a pleted and died insert I2, the enveloping and manner to produce a satisfactory and adequate bonding rubber sheet of carbon b1ack stock I4, 10 bond therebetween. and the backing rubber sheet I6. After assembly In the accompanying drawing illustrating the the combined structure is placed in a mold in the preferred form of the invention, Fig. 1 repreusua1 manner and subjected 110 vulcanizing heat sents the component parts of such a sole ready for and pressure, care being taken that the face with 10 assembly; and Fig. 2 represents the assembled the rubber overlay is put in the mold in a manner product ready for vulcanizing in a mold. to form the attaching face of the sole, whereas the In the manufacture of soles and heels through opposite face exposes the insert with theendwise the employment 015 pleated friction material such projection of fibres.

as shown in Quinn Patent N0. 1,935519 or its What is claimed is: v zu equivalent I have found. that in attempting to The method of producing a tread member of bond such an insert t0 sole stock of certain disrubber compound with a friction insert, which similar compositions normally employed for this consists in dieing out a sole blank of rubber compurpose, very considerable difi1culty is encounpound With an opening to receive the insert, pretered. In fact, this difliculty is so great that the paring a friction insert of a shape and dimensions use of such an insert in other than carbon black to be received within the opening, the insert comcomposition soles has been heretofore considered prising a fibre rubber compound with the fibres impractical. presented generally endwise 130 the face, as-

According to my invention, I produce an insert sembling with the insert a sheet of carbon black by first forming a sheet with parallel fibres thererubber stock which covers one face and the margi- O in, isombining the sheet with gum rubber stock, na1 edge of the insert. assembling the insert with pleating the combined sheet, and thereafter splitthe died out sole blank With the carbon black sing 130 produce two split sheets of equal thicksheet interposed between the edges 0f the insert ness. These are then dinked out into the proper and the sole blank, applying a backing sheet form for an insert. I combine with this dinkedwhich covers one face of the sole blank and the out insert a thin sheet of uncured carbon black carbon blank sheet, and finally subjecting the asrubber stock which is turned up about the edge of semblecl article to vulcanizing heat and pressure the insert and forms a complete insertion between in a mold. the edges of the insert and. the surrounding sole ARTHUR GREENBAUM. blank. T0 the bottom of the insert thus treated 

